Defending Partly Intrinsic Taxon Essentialism

Abstract Chapter 1 went against the consensus in the philosophy of biology by arguing that Linnaean taxa, including species, have essences that are partly intrinsic underlying, probably largely genetic, properties: biological generalizations about the phenotypic properties of taxa require explanations that must advert to these essences. The present chapter responds to criticisms of that argument. My responses emphasize three distinctions: between structural and historical explanations, which is central to my argument for intrinsic essentialism; between the category and the taxon problems, which is central to my rejection of the main argument against intrinsic essentialism; between the conspecificity and taxon problems, which is central to my diagnosis of where the consensus has gone wrong. I deny that my essentialism is at odds with certain biological variations and that its talk of intrinsic essences is an uncalled for metaphysical addition to biology.